1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a backlight assembly for increasing a usage efficiency of light generated by a lamp to enhance brightness of light with a lower consumption of electricity and a liquid crystal display device using thereof.
2. Description of the Related Art
In generally, In the liquid crystal display device, a thin film transistor substrate is provided in which a desired voltage is selectively applied to divided regions thereof having a fine area respectively and a color filter substrate is disposed in which a regular voltage is applied to a whole area thereof. Liquid crystal is introduced between the thin film transistor substrate and the color filter substrate of which a permeability of light is changed with depending on a change of an electric filed between the thin film transistor substrate and the color filter substrate. The voltage corresponding to image data is selectively applied to the divided regions of the thin film transistor substrate in order for the liquid crystal display device to display the images.
The liquid crystal is an element that does not radiate but receive the light, which carries out changing only the permeability of the light according to the change of the electric field between the thin film transistor substrate and the color filter substrate.
It means that the light is required to display the images with correspondence to the image data provided for the liquid crystal display device.
The light required to display the images in the liquid crystal display device is supplied by a natural light source such as sunlight or an artificial light source using electric energy.
When displaying the images is performed by using the natural light source, the liquid crystal display device is light in weight and small in size as a separate device using the electric energy is unnecessary for generating the light. In this case, however, there is a disadvantage in that the liquid crystal display device cannot display the images in the dark.
While it is performed to display the images by using the artificial light source, the liquid crystal display device can display the images anywhere regardless of darkness and brightness. In this case, however, there are disadvantages in that a consumption of electricity increases and the light crystal display device is heavy in weight and large in size.
Especially, when it is taken in consideration that the liquid crystal display device is made for a portable usage, the consumption of the electricity in the liquid crystal display device using the artificial light source is very important. In recent, accordingly, researches have been performed to reduce the consumption of the electricity in the liquid crystal display device even though the artificial light source is adopted to the liquid crystal display device.
Recently, it tends to improve a brightness of the light and a uniformity of the brightness of the light by forming V-shaped grooves or printing reflection dots on a bottom surface of the light guide plate that converts a line light source type of light into a surface light source type of light and changes a pathway of the light emitted from the lamp.
When the brightness of the light is improved and the consumption of the electricity is reduced in the liquid crystal display device in such a manner as described above, the efficiency of the light is deteriorated and it is more difficult to further reduce the electricity consumption. Accordingly, it is required for a backlight assembly capable of increasing a usage efficiency of light generated by a lamp to enhance brightness of light with a lower consumption of electricity.